<!doctype html>
<html>
<head>
  <meta charset="utf-8">
  <title><%=title %> </title>
</head>
<body>
  <div>
    <form enctype="multipart/form-data" method="post" action="/upload">
      <br/>
      File:<input type="file" id="_file" name="_file" style="width:400px;height:35px;" onchange="fileSelect()" />
      <br/>
      <!-- 仅仅在使用multer。array时候 -->
      <!-- <input type="file" id="_file1" name="_file" style="width:400px;height:35px;"/>
      <input type="file" id="_file2" name="_file" style="width:400px;height:35px;"/> -->
      <input type="submit" value="submit" style="width:100px;height:35px;" />
      <br/>
    </form>
  </div>
</body>

<script>
  function fileSelect () {
    const files = document.getElementById('_file').files;
    console.log(files);
  }
  </script>

</html>